Field effect device with a channel with a switchable conductivity

Abstract

A field effect device ( 2 ) includes a source electrode ( 14 ), a drain electrode ( 16 ), a channel ( 24 ) formed between the source electrode ( 14 ) and the drain electrode ( 16 ), and a gate electrode ( 22 ) separated from the channel ( 24 ) by an insulating layer ( 20 ), wherein the channel ( 24 ) comprises a switching material reversibly switchable between a lower conductivity state and a higher conductivity state, each of the conductivity states being persistent.

1. A field effect device comprising:
 a source electrode; 
 a drain electrode spaced laterally apart from the source electrode; 
 a channel formed between the source electrode and the drain electrode; and 
 a gate electrode formed directly on the channel and arranged in a gap between the source electrode and the drain electrode, 
 wherein the channel comprises a switching material reversibly switchable between a first conductivity state and a second conductivity state, the first conductivity state having a conductivity which is lower than a conductivity of the second conductivity state, each of the conductivity states being persistent; 
 wherein the switching material comprises at least one compound selected from the group consisting of chalcogenide, SrTiO 3 , SrZrO 3 , BaSrTiO 3 , Ta 2 O 5 , Ca 2 Nb 2 O 7 , and a material comprising at least one of a perovskite and a perovskite-like crystal structure, the material being doped up to 20% with a dopant. 
 
     
     
       2. The field effect device according to  claim 1 , wherein the switching material is switchable between the first conductivity state and the second conductivity state by application of a predetermined voltage between the source electrode and the drain electrode or between the gate electrode and at least one of the source electrode and the drain electrode. 
     
     
       3. The field effect device according to  claim 1 , wherein the switching material at least forms one of a filament within the channel and a part of the channel. 
     
     
       4. The field effect device according to  claim 1 , wherein the switching material is switchable between the first conductivity state and the second conductivity state by at least one of injection and extraction of charge carriers in the device. 
     
     
       5. The field effect device according to  claim 1 , wherein the switching material is switchable between the first conductivity state and the second conductivity state by application of a voltage or a current to the switching material of the channel. 
     
     
       6. The device according to  claim 1 , wherein the dopant comprises at least one of Chromium (Cr), Vanadium (V), and Manganese (Mn).